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水库和坝对动水压力的影响

世界地震工程 1986年第4期 49-54页

作者： d.k.paul 祁建华

前言在大坝抗震设计中,动水压力是一个重要因素。库水的可压缩性、坝的柔性、水库形状、坝形和悬浮或沉积在上游坝面的淤泥都是影响动水压力的因素。本文研究了水库和大坝形状对坝体反应和动水压力的影响。这里采用了删去由于完全不对... 详细信息

前言在大坝抗震设计中,动水压力是一个重要因素。库水的可压缩性、坝的柔性、水库形状、坝形和悬浮或沉积在上游坝面的淤泥都是影响动水压力的因素。本文研究了水库和大坝形状对坝体反应和动水压力的影响。这里采用了删去由于完全不对称矩阵所产生的无效项的分块求解方案。本程序将坝体和库水考虑为两个单独的场,在接触面上两个场连续地相互作用着。在水库有限元分析中,采用了欧拉系的位势公式,其中考虑水是无粘性的、无旋的和可压缩的。对于棍凝土坝,用二维平面应力有限元离散,在时域中计算坝和库水系统的瞬

关键词：方程库水水库单位脉冲向量动水压力

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抗震设计准则

世界地震工程 1982年第Z1期 113-118+30页

作者： Jai krishna Brijesh Chandra d.k.paul 陈达生

序言当重要的结构物位于地震区时,就需要建立可靠的设计准则以考虑未来地震对结构施加的力。统观世界上的记录,似乎还找不到曾经发生强震的地方,其地质构造和地基条件,与新结构物修建的地点几

关键词：地面运动特性震源深度地震基本参数峰值地面加速度谱强度谱烈度地震参数加速度记录地震活动性震级设计准则

Evidence supporting the relationship between maternal asthma and risk for autism spectrum disorders

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Neural Regeneration Research 2025年第4期20卷 1101-1102页

作者： Hadley Osman paul Ashwood department of Medical Microbiology and Immunology and the M.I.N.D.InstituteUniversity of California at DavisSacramentoCAUSA

during pregnancy,maternal immune activation(MIA),due to infection,chronic inflammatory disorders,or toxic exposures,can result in lasting health impacts on the developing *** has been associated with an increased risk of neurodevelopmental disorders,such as autism spectrum disorder(ASd)in the *** is characterized by increased repetitive and stereotyped behaviors and decreased *** of 2020,1 in 36 children are diagnosed with ASd by the age of 8 years,with ASd rates continuing to increase in prevalence in USA(Tamayo et al.,2023).Post-mortem brain studies,biomarker and transcriptomic studies,and epidemiology studies have provided compelling evidence of immune dysregulation in the circulation and brain of individuals diagnosed with ***,the etiology of ASd is largely unknown,however,genetic components and environmental factors can contribute to increased *** allergic asthma(MAA),a form of MIA,has been identified as a potential risk factor for developing neurodevelopmental disorders(Patel et al.,2020).Asthma is a chronic inflammatory condition driven by a T-helper type(TH)2 immune response.

关键词： disorders epidemiology fetus

Emerging insights into the function of very long chain fatty acids at cerebellar synapses

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Neural Regeneration Research 2025年第6期20卷 1709-1710页

作者： Martin-paul Agbaga Mohiuddin Ahmad department of Cell Biology and Ophthalmology University of Oklahoma Health Sciences Centerand Dean McGee Eye InstituteOklahoma CityOKUSA

Very long chain-saturated and-polyunsaturated fatty acids(VLC-SFA and VLC-PUFA, respectively) are a functionally important class of fatty acids containing 28 carbons or more in their acyl chain. They are synthesized by the elongation of very long fatty acids-4(ELOVL4) enzyme, expressed mainly in the brain, retina, skin, testes, and meibomian gland, where these fatty acids are found(Agbaga et al., 2008). Further, these organs exhibit tissuespecific VLC-PUFA and VLC-SFA biosynthesis and incorporation into complex lipids for specific functions. In the brain, skin, and Meibomian glands, the ELOVL4 mainly makes VLC-SFA, which are incorporated into complex sphingolipids. In the retina, the ELOVL4 makes VLC-PUFA that are incorporated into phosphatidylcholine, that are critical for visual function, while in testes and sperm, the VLC-PUFA are incorporated into sphingolipids that are critical for fertility(Yeboah et al., 2021).

关键词： functions function insight

功函促进钼基异质结电催化剂的电子结构重整提升其析氢反应活性（英文）

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Science China Materials 2025年第1期 189-198页

作者：陈想冯帅谢松苗亚萍高标张旭明黄莉李筠 paul k.Chu 彭祥 Hubei key Laboratory of Plasma Chemistry and Advanced Materials Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education School of Materials Science and Engineering Wuhan Institute of Technology School of Textile Science and Engineering Xi'an Polytechnic University The State key Laboratory of Refractories and Metallurgy Institute of Advanced Materials and Nanotechnology Wuhan University of Science and Technology Guizhou Wujiang Hydropower development Co. Ltd. department of Physics Department of Materials Science and Engineering and Department of Biomedical Engineering City University of Hong Kong

Mo基催化剂在电催化析氢反应（HER）中具有巨大应用潜力.然而,其活性位点的暴露不足、极强的氢吸附能力导致其催化性能未能充分体现.本文在碳布上构筑了Mo2N–MoSe2异质结（MNS）,以增强Mo基催化剂的HER活性.由于MNS中的Mo2N具有较低的...

Mo基催化剂在电催化析氢反应（HER）中具有巨大应用潜力.然而,其活性位点的暴露不足、极强的氢吸附能力导致其催化性能未能充分体现.本文在碳布上构筑了Mo2N–MoSe2异质结（MNS）,以增强Mo基催化剂的HER活性.由于MNS中的Mo2N具有较低的功函数,能够在异质界面产生内建电场,显著提高了其在HER中电荷转移效率.此外,MNS中原子之间的强电子相互作用优化了Mo位点的电子结构,降低了氢吸附能力,进一步增强了其本征催化活性.因此, MNS催化剂产生20 m A cm-2和1 A cm-2的析氢电流密度所需的过电位仅为65和210 mV, Tafel斜率仅为96 mV dec-1.此外, MNS在1 A cm-2电流密度下稳定运行240小时后,形貌、结构和性能均无明显变化.以上研究结果为工业大电流制氢所需的非贵金属基电催化剂的设计和合成提供了新思路.

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distinct expression profiles of transcriptional coactivators for thyroid hormone receptors during Xenopus laevis metamorphosis

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Cell Research 2003年第6期13卷 459-464页

作者： BINdU d paul National Institutes of Health Laboratory of Gene Regulation and development National Institute of Child Health and Human development Bldg. USA.

The biological effects of thyroid hormone (T3) are mediated by the thyroid hormone receptor (TR). Amphibian metamorphosis is one of the most dramatic processes that are dependent on T3. T3 regulates a series of orchestrated developmental changes, which ultimately result in the conversion of an aquatic herbivorous tadpole to a terrestrial carnivorous frog. T3 is presumed to bind to TRs, which in turn recruit coactivators, leading to gene activation. The best-studied coactivators belong to the p160 or SRC family. Members of this family include SRC1/ NCoA-1, SRC2/TIF2/GRIP1, and SRC3/pCIP/ACTR/AIB-l/RAC-3/TRAM-1. These SRCs interact directly with liganded TR and function as adapter molecules to recruit other coactivators such as p300/CBP. Here, we studied the expression patterns of these coactivators during various stages of development. Amongst the coactivators cloned in Xenopus laevis, SRC3 was found to be dramatically upregulated during natural and T3-induced metamorphosis, and SRC2 and p300 are express

关键词： transcription coactivators thyroid hormone receptor Xenopus laevis metamorphosis histone acetylation.

Increased Light, Moderate, and Severe Clear-Air Turbulence in Response to Climate Change

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Advances in Atmospheric Sciences 2017年第5期34卷 576-586页

作者： paul d. WILLIAMS department of Meteorology University of Reading Reading RG6 6BB United Kingdom

Anthropogenic climate change is expected to strengthen the vertical wind shears at aircraft cruising altitudes within the atmospheric jet streams. Such a strengthening would increase the prevalence of the shear instabilities that generate clear-air turbulence. Climate modelling studies have indicated that the amount of moderate-or-greater clear-air turbulence on transatlantic flight routes in winter will increase significantly in future as the climate changes. However,the individual responses of light,moderate,and severe clear-air turbulence have not previously been studied,despite their importance for aircraft operations. Here,we use climate model simulations to analyse the transatlantic wintertime clear-air turbulence response to climate change in five aviation-relevant turbulence strength categories. We find that the probability distributions for an ensemble of 21 clear-air turbulence diagnostics generally gain probability in their right-hand tails when the atmospheric carbon dioxide concentration is doubled. By converting the diagnostics into eddy dissipation rates,we find that the ensembleaverage airspace volume containing light clear-air turbulence increases by 59%(with an intra-ensemble range of 43%–68%),light-to-moderate by 75%(39%–96%),moderate by 94%(37%–118%),moderate-to-severe by 127%(30%–170%),and severe by 149%(36%–188%). These results suggest that the prevalence of transatlantic wintertime clear-air turbulence will increase significantly in all aviation-relevant strength categories as the climate changes.

关键词： turbulence climate change aviation jet stream

High-resolution geological maps of central London, Uk： Comparisons with the London Underground

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Geoscience Frontiers 2016年第2期7卷 273-286页

作者： Jonathan d. paul department of Earth Sciences Bullard Laboratories University of Cambridge Madingley Rise Cambridge CB3 0EZ UK

This study presents new thickness maps of post-Cretaceous sedimentary strata beneath central London. 〉1100 borehole records were analysed. London Clay is thickest in the west; thicker deposits extend as a narrow finger along the axis of the London Basin. More minor variations are probably governed by periglacial erosion and faulting. A shallow anticline in the Chalk in north-central London has resulted in a pronounced thinning of succeeding strata. These results are compared to the position of London Underground railway tunnels. Although tunnels have been bored through the upper levels of London Clay where thick, some tunnels and stations are positioned within the underlying, more lithologically variable, Lower London Tertiary deposits. Although less complex than other geological models of the London Basin, this technique is more objective and uses a higher density of borehole data. The high resolution of the resulting maps emphasises the power of modelling an expansive dataset in a rigorous but simnle fashion.

关键词： London London Underground London Clay Lambeth Group Chalk Tunnelling Boreholes

Active catalytic species generated in situ in zirconia incorporated hydrogen storage material magnesium hydride

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Journal of Magnesium and Alloys 2022年第3期10卷 852-861页

作者： d.Pukazhselvan k.S.Sandhya devaraj Ramasamy Aliaksandr Shaula Igor Bdikin duncan paul Fagg department of Mechanical Engineering Nanoengineering Research GroupCentre for Mechanical Technology and Automation(TEMA)University of AveiroAveiro 3810-193Portugal department of Chemistry Malankara Catholic CollegeKaliyakkavilaiTamil Nadu 629153India department of Computational Biology and Bioinformatics University of KeralaThiruvananthapuramKerala 695581India UIdM ESTGPolytechnic Institute of Viana do CasteloViana do Castelo 4900Portugal

This study explores how zirconia additive interacts with MgH_(2)to improve its hydrogen storage *** it is confirmed that the zirconia added MgH_(2)powder releases hydrogen at a temperature of about 50℃below that of the additive free MgH_(2).Subsequent tests by X ray diffraction(XRd)and infrared(IR)spectroscopy techniques reveal that the ZrO_(2) mixed MgH_(2)powder contains ZrHx(21.5)and MgO secondary *** observation is supported by the negative Gibbs free energy values obtained for the formation of ZrH_(2)/MgO from ZrO_(2)/MgH_(2)powder *** X ray photoelectron spectroscopy(XPS)study reveals that apart from Zr^(4+)cations,Zr^(2+) and zero valent Zr exist in the *** force microscopy(AFM)study reveals that the average grain size is 20 nm and the elemental line scan profiles further proves the existence of oxygen deficient Zr bearing phase(s).This study strengthens the belief that functional metal oxide additives in fact chemically interact with MgH_(2)to make active in-situ catalysts in the MgH_(2)system.

关键词： Hydrogen storage Binary hydrides Metal oxides Additives Nanocatalysis.